It appears NeatherRealm Studios, the company that is developing the upcoming Mortal Kombat XI fighting game, is interested in enabling cross-platform multiplayer in their new game, due for release this Spring. This could enable users on various platforms such as Xbox One, PC and Mac to not just play with each other, but also interact with cross-platform profiles, friends, voice communication, and match-making, cloud saves and even achievements could work between the different platforms
All of this could be possible in part due to Epic Games' release of their API tools, as spotted by the writers at Wccftech. The gaming company that develops the heavily popularized and highly cross-compatible Fortnite game will make new cross-platform features free for all developers, and the APIs will be released over a period of several months for any developer wishing to incorporate them into their own titles.
- Cross-Platform Login, Friends, Presence, Profile, and Entitlements (coming Q2-Q3 2019 to PC, other platforms throughout 2019): Provides the core functionality for persistently recognizing players across multiple sessions and devices; identifying friends; and managing free and paid item entitlements. This will support all 7 major platforms (PC, Mac, iOS, Android, PlayStation, Xbox, Switch) to the full extent each platform allows per-title.
- PC/Mac Overlay API (coming Q3 2019): Provides a user interface for login, friends, and other features in a game-agnostic, engine-agnostic way.
- Cross-Platform Voice Comms (coming Q3 2019 to all platforms): Epic is building a new in-game voice communications service supporting all platforms, all stores, and all engines, which will be available for free. (For developers needing an immediately-available voice solution, check out Discord, Vivox, TeamSpeak, Ventrilo, and Mumble.)
- Cross-Platform Parties and Matchmaking (coming Q3-4 2019 to all platforms)
- Cross-Platform Data Storage, Cloud-Saved Games (coming Q2 2019)
- Cross-Platform Achievements and Trophies (coming Q3 2019)
Cross-platform multiplayer is unlikely to be available in the game's initial release in April 23, and the developers haven't addresses much, including whether the game could work between PS4 and other platforms. This is likely due to Sony's strict policies against cross-play, however lately it seems to be willing to soften its stance on the issue.
If you're interested, the game is available for pre-order right now on the Microsoft Store, and will be an Xbox One X Enhanced title and supports HDR10 for anyone who is sporting a supported TV and Xbox One S or X system.